The invention relates to an X90 pipeline steel wide and thick plate and a production method thereof, belonging to the technical field of low-carbon microalloy steel. The wide and thick plate comprises the following components in percentage by weight: 0.06-0.10% of C, 0.20-0.50% of Si, 1.50-1.80% of Mn, at most 0.010% of P, at most 0.003% of S, 0.04-0.06% of Nb, 0.04-0.06% of V, 0.010-0.020% of Ti, 0.15-0.30% of Ni, 0.15-0.30% of Cr, 0.10-0.30% of Mo, 0.020-0.05% of Als, and the balance of Fe and inevitable impurities. The technique comprises the following steps: predesulfurizing blast furnace molten iron, smelting in a converter, carrying out LF+RH refinement, continuously casting a plate blank, heating the plate blank, rolling by a 4300 rolling mill, carrying out ACC quick cooling, cooling in pile, sampling, inspecting, warehousing and shipping. The steel plate has the advantages of high strength, excellent low-temperature toughness and excellent dynamic tear resistance.